Radio Frequency Identification (RFID) systems have been proposed for the tracking of medical supplies in hospitals. Such systems typically involve one or more readers and many tags, each of which is attached to an item being monitored. In the case of medicaments, single-use medical devices, and implantable medical devices, RFID tags are typically affixed to or made part of the medicament container, e.g. medicine bottle, or medical device container, e.g., disposable packaging for the stent or orthopedic implant.
RFID tags take the form of integrated circuits, with associated antennas, that encode a unique serial number. The reader is generally in a fixed location, and items with RFID tags are detected when they enter or leave the electromagnetic field of the reader. For example, RFID readers are often placed at multiple distributed locations associated with an item's supply chain in order to monitor the item as it passes through manufacturing, transportation, and distribution. Each reader captures the RFID tag serial numbers of each item as it enters the reader's interrogation field, and data collected from all readers facilitate item tracking over time, through the chain.
Tracking using these systems generally deteriorates as the items being tracked approach the time and place of use, e.g., consumption, implantation, exhaustion, or disposal. It is therefore difficult to trace a particular item's full history.
For example, the most common practice in accounting for product use and disposition is based on manual data entry, sometimes assisted by bar-code scans. These manual procedures record the usage and disposition of supplies. Moreover, data entry often must be performed under time constraints that do not allow verification of the data entered. Consequently, error rates can be high and data quality is often poor. Indeed, the personnel performing these procedures often do not recognize them as high-priority tasks.